Jack-truck.



G. W. TRAMBLEY.

JACK TRUCK.

APPLICATION FILED FEB-23,1917.

Patented Sept. 11, 1917.

G. W. TRAMBLEY.

JACK TRUCK.

APPLICATION FILED FEB. 23. 1917.

Patented Sept. 11,1917.

2 SHEETSSHEEI 2.

onnron.

GEORGE W. 'I'RAMBLEY, OF CHICAGO, ILLINOIS, ASSIGNOR F ONE-THIRD T0 JOHN W, FARLEY, OF CHICAGO, ILLINOIS.

JACK-TRUCK.

Specification of Letters Patent.

Patented Sept. 11, 1917.

Application filed February 23, 1917. Serial No. 150,384.

useful Improvements in Jack-Trucks, of

which the following is a specification.

This invention relates to hand trucks, and

more particularly to jack trucks, which. are designed to both lift and transport a load. The principal object of the invention is to provide a truck which may be readily backed beneath a heavy piece of furniture, a machine, or any other article that is supported by legs or otherwise from the floor, and, by a simple upward swing of the tongue, or like draft member, may be caused to lift and carry such article in a manner enabling the latter to be transported to any desired place of deposit, and then lowered onto the floor, the truck'being then withdrawn from be neath the load. 7 f l One practical form in which my inven tion may be embodied is illustrated in the accompanying drawings, in which I Figure 1 is a top plan view of the truck in load-carrying position, the tongue being broken ofi r Fig. 2 is a longitudinal section on the line 2-2 of Fig. 1;

Fig. 3 is a detail section onthe line 33 of Fig. 1;

Fig. 4 is a fragmentary side elevation of therear portion of the truck;

Fig. 5 is a view, partly in side elevation and partly in longitudinal section, showing the truck in lowered or collapsed position;

it employs a pair of rectangular frames,the'

upper of which, that carries .the load, is mounted upon the lower through the agency of pivoted links, which maintain the two frames in parallelism in all positions. A tongue connectedto one of the frames serves not only for draft purposes, but also as a lever'to effect the expansion of the frames and the consequent raising of the upper frame, and a manually releasable automatic locking device secures the two frames in fully expanded position the instant that position is reached in the frame-expanding operation. The connecting links of the frames are slightly off vertical in the fully raised position of the upper frame, so that when the lock is released the weight of the load at once collapses the two frames. Suit able wheels or rollers are provided at the corners of the lower frame, the front wheels preferably being trailing casters for the purpose of easy steering. In the embodiment of the invention herein shown, the side and end members of the lower frame are jointed through the agency of portions of the connecting links, but this does not affect the principle. of the construction, which is capable of embodiment in a construction employing a rigid underframe.

Referring to the drawings, 10 designates the longitudinal side bars, 11 the rear cross bar, and 12 the front cross bar of the lower frame, the side bars having a jointed connection with the rear cross bar 11 through the agency of the lower portions 13 of a pair of rear links 13, and the side bars having a jointed connection with the front'cross bar through the agency of upwardly extending portions 14 of a pair of front links 14. The upper or load-carrying frame, as herein shown, comprises a pair of parallel side bars 15 rigidly connected and spaced by intermediate transverse rods 16, and front and rear transverse end bars 17 and 18, respectively, the former extending between and rigidly secured in the forward links 14, and the latter extending between and rigidly secured in the rear links 13. The side bars 15 and their connecting rods 16 are preferably made removable from the end bars 17 and 18 by means of notches 19 in the lower sides of the bars 15 straddling said end bars 17 and 18 in the manner clearly shown in Fig. 3.

Mounted on axles 20 extending outwardly from the lower ends of the rear links 13 are wheels or rollers 21; while. the forward links 14 are formed with laterally extending flanges 22,0n the under sides of which are suitably mounted trailing casters 23.

To look the two relatively expansible and collapsible frames in expanded or load carrying position, I provide apair of bars 24 that are pivoted at 25 to the inner sides of the side bars 10 of the lower frame and,.at their forward ends, are notched on their lower edges to provide hooks 26 that are adapted to engage the forward cross bar 17 of the upper frame so as to hold said frames against relative movement toward each other. Preferably, and as herein shown, the free ends of the locking bars 24 are connected by a bail-shaped handle 27, which facilitates manual release of the locking bars when the load is to be lowered.

In order to render this locking device automatic upon the completion of the expanding movement of the two frames, I pro vide a tension spring 28, the upper end of which is connected to the handle 27, while its lower end is anchored to a short arm 29 that is fast on the cross bar 17.

In order to limit the expanding movement of the frames to an extent wherein the connecting links will be slightly off vertical, so as to insure the dropping of the load when the lock is released, I provide on either or.

both of the side bars 15, a stop lug or lugs 30 that are engaged by the upper ends of the links 13 just before the latter reach avertical position. The downward Or'col .lapsing movement is limited by apair of links 14 is the hound 33 of a draft pole or tongue 84 that is provided at its outer end with an ordinary cross bar 35 forming a handle. Slidably mounted in brackets 36 on the upper side of the tongue 34 is a rod 37, the. lower end of which is adapted to engage with an aperture 38 in the cross bar 12 in the fully-raised position of the tongue to support the latter in such position, as shown in Fig. 2; this rod being provided at its outer end with an operating handle 39.

Theoperation will be readily understood from the foregoing description, but may be briefly described as follows: i

When a heavy ai'ticle, such forinstance as astove, is to be transferred from one place to another, the jack truck, in the collapsed position illustrated in Fig. 5, is backed beneath the stove, and thc tongue is then swung upwardly. During this movement, the homid portion of the tongue engages the forward cross bar 12 of the lower frame structure, and acts as a lever to rock the forward links 14 upwardly to the approximately vertical position shown in Fig. 2;

corresponding movement is. imparted tothe rear links 13 through the connecting side bars ofthe two frames; and, as soon as the cross rod 17 comesbeneath the hooks 26 of the locking bars, the tension of the spring 28 instantly draws said hooks into engagement with the cross rod 17, and thereby locks the two frames in expanded position against the tendency of the weight of the load to collapse them. At the same time, the stop deposit. VVhen this is reached, theoperator lowers the tongue to the ground or floor, as shown in Fig. 5, lifts the handle 27, thus releasing the lock, and the weight of the. load instantly causes the frames to collapse,

bringing the article into engagement with the floor through its legs or other'supports, so that the truck may be readily drawn out from beneath the same. I

It willbe observed that asthe truck co1- lapses, the forward rod 17 carrying the anchorage arm 29of the spring 28 turns in a counter-clockwise direction from the position shown in Fig. 2 to that shown in Fig. 5, thereby raising the lower end of the spring, and thus preventingunnecessary stretching of the latter .duringthe collapsing operation. a V

In Figs. 2 and 5, I have indicated in dotted lines a board or platform 40 which t may be remov'ably applied to the 'top' of the upper skeleton frame for carrying small articles, whenthe truck is used simply as a transportation truck, said board or platform conveniently being provided on its under side with longitudinalcleats 41 formed with notches 42 straddling the cross rods 16. V

As the truck does not have a pivoted or swinglng front axle, the provisionjof tralllng casters at the forward corners of the truck enables the latterto be. readily steered,

these casters being self-righting during the lifting or expanding movement of the truck.

It is believed that the foregoing description will make clear to those skilled 'in this art the construction, mode of operation, and

advantages of the invention; and, without limiting myself to the precise details herein shown and described,--- i I claim: p y 1, In ajack truck, thejcombination of two substantially parallel horizontal frames,

links pivotally connectingthe adjacent ends of said frames, wheels on the lower ends of sald llnks, a tongue connected to oneof sald frames and serving, when lifted, to effect the expansion of said frames, and manually releasable automatic means for locking said frames in expanded position comprising a pair of locking bars pivoted tothe side members of one frame and haring hooks engage able with an'elementof the other frame, a handle-bar connecting said locking bars, and

a spring connected to said handle bar and normally urging saidhojoks into locking position.

2. In a jack truck, the combination of two substantially parallel horizontal frames, links pivotally connecting the adjacent ends of said frames, wheels on the lower ends of said links, a tongue connected to one of said frames and serving, when lifted, to effect the expansion of said frames, and manually releasable automatic locking means for looking said frames in expanded position comprising a locking member pivoted to one of said frames and having hooking engagement with an element of the other frame, a tension spring connected at one end to said locking member, and a movable anchor member for the other end of said spring, said anchor member operating to decrease the tension of said spring as the frames are collapsed and to increase its tension as the frames are expanded.

3. In a jack truck, the combination of two substantially parallel horizontal frames, a pair of links pivotally connecting the rear ends of said frames, wheels on the lower ends of said links, a pair of links pivotally connecting the forward ends of said frames and having upwardly extended portions, one of said frames having a cross-bar rigidly connecting the upper ends of said last-named links, wheels on the lower ends of said lastnamed links, a tongue pivoted to said lastnamed links and adapted, when swung up wardly, to cooperate as a lever with said cross-bar through direct engagement with the latter to effect the expansion of said frames, and means for automatically locking said frames in expanded position.

4. In a jack truck, the combination of two substantially parallel horizontal frames, a pair of links pivotally connecting the rear ends of said frames, wheels on the lower ends of said links, a pair of links pivotally connecting the forward ends of said frames and having upwardly extended portions, one

of said frames having an apertured crossbar rigidly connecting the upper ends of said last-named links, a tongue pivoted to said lastnamed links and adapted, when swung upwardly, to cooperate as a lever with said cross-bar to effect the expansion of said frames, means for automatically locking said frames in expanded position, and a locking rod slidably mounted on said tongue and adapted to enter the aperture of said crossbar to hold said tongue in elevated position.

GEORGE W. TRAMBLEY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

